Reciprocating die press



Sept. 8, 1953 F. E. STRATTON EI'AL RECIPROCATING DIE PRESS 10 Shets-Sheet 1 Filed March 29, 1949 [nvento PS Rank E. Sirafzod Hbrazio VHa/Z By U: it"

Sept. 8, 1953 F. E. STRATTON arm. 2,651,365

RECIPROCATING DIE PRESS 10 Sheets-Sheet 2 Filed March 29, 1949 [TI van/tors Eank E. SZr-afton Horazio V Hall Se t. 8, 1953 F. E. STRATTON ETAL 2,651,365

RECIPROCATING DIE PRESS Filed March 29, 1949 10 Sheets-Shet :5

F. E. STRATTON EI'AL 2,651,365 RECIPROCATING DIE PRESS Sept. 8, 1953 Filed March 29, 1949 10 Sheets-Sheet 4 [n UE'TZZ O 15' Frank E. Szrafzan F. E. STRATTON EI'AL 2,651,365

RECIPROCATING DIE PRESS Sept. 8, 1953 Filed March 29, 1949 10 Sheets-Sheet 5 I I I 1 Inventors Rank 5 Siraz/LOn Horczzz o V Hall y {he p 1953 F. STRATTON ETAL 2,651,365

RECIPROCATING DIE PRESS Filed March 29, 1949 10 Sheets-Sheet e Inv e nto P3 Frank E SZra zfon Sept. 8, 1953 F. E. STRATTON ETAL 2,651,365

I RECIPROCATING DIE PRESS Filed. March 29, 1949 10 Sheets-Sheet 7 Inventors Frank E. Sir-a Zton Sept. 8, 1953 F. E. STRATTON EI'AL 2,651,365

RECIPROC'ATING DIE PRESS Filed March 29, 1949 l0 Sheets-Sheet 8 320 332 328 I j?" 9330 33 3/5 I 1 2 I o 34:: {J Inventors r: Frank fisi'r'zzzorz/ 33 5 Horqfz o VHa/Z [6 79.11. Byz A! ey Sept. 8, 1953 F. E. STRATTON in AL 2,651,365

RECIPROCATING DIE PRESS Filed March 29, 1949 10 Sheets-Sheet 9 fnz/en ions Frqnk ESzrahon Patented Sept. 8, 1953 2,651,365 RECIPRO CATIN G DIE PRESS Frank E.

Mass., assignors to Corporation, of New Jersey Stratton and Horatio V. Hall, Beverly,

United Shoe Flemington,

Machinery N. J., a corporation Application March 29, 1949, Serial No. 84,176

Claims.

This invention relates to presses, and more particularly to presses of the type commonly referred to as clicking machines, employed for cutting shoe part blanks from leather or fabric.

In such machines, as heretofore constructed, use has been made of mechanism including a platen or cutting block for supporting sheet material to be operated upon, a freely movable die which can be located upon the material, and a beam movable over the block into position above have been devised for effecting the relative movement between the cutting block and the beam, and several of them have been highly successful from a commercial standpoint.

An object of the present invention is to provide an improved machine of the type referred to in which the mechanism for causing relative movement between the beam and cutting block is particularly effective in its operation to the ends of producing accurate cutting of blanks with low power consumption and low vibration transmission to the immediate surrounding of the machine, while, at the same time, one which will be easy and safe to operate as well as economical to service.

In view of this, the invention as herein illustrated provides a press in which there is a platen for supporting sheet material and a cutting die, and a beam movable across the platen into operative position over the die, together with means for moving the platen toward and away from the beam and for effecting a rolling movement of the platen along the beam progressively to force the die through the material in producing a blank. Preferably, and as shown, the movement of the platen is efiected partly by means of toggles which are arranged to raise the platen toward the beam, there being additional means, herein illustrated as a cam controlled platen constraining member, cooperable with the toggles to guide the platen in its rolling movement. Preferably, and as shown, there are also provided manually operable starting means associated with the beam and so constructed and arranged that it is necessary for the operator to use both hands in initiating a power operation of the machine, thus insuring that his hands are in a safe position during operation of the platen. As disclosed herein this mechanism takes the form of two manual controls, operation of both of which is required to close an electric circuit through a solenoid operable to initiate a power operation of the toggles. Repetition of a power operation is prevented by means of electrical devices until both of the manual controls have been released, thus preventing unauthorized jamming of the safety mechanism.

operating with the beam in progressively forcing a die through the material to be operated upon in producing a blank.

These and other objects and features of the in the following specification and in the accompanying drawings and are pointed out in the appended claims.

Fig. 1 is a View in end elevation, partly in section, illustrating one embodiment of the clicking machine constituting our invention;

Fig. 2 is a front elevation, partly in section, of the right-hand portion of the machine illustrated in Fig. 1;

Fig. 3 is a front elevation, partly in section, of the left-hand portion of the machine illustrated in Fig. 1;

Fig. 4 is a sectional view taken along the line IV-IV of Fig. 1'

Fig.5 is a side drive shaft and its associated mechanism;

Fig. 6 is a vertical sectional view taken along the lines VI-VI of Fig. 3;

Fig. 7 is a side view, partly in section, of resetting mechanism for the control of power operation of the machine;

Fig. 8 is a side view, partly in section, of the post and its associated height adjusting mech-- anism;

Fig. 9 is a plan view, partly in section, of the manually operable starting mechanism;

Fig. 10 is a front elevation, partly in section, of the mechanism shown in Fig. 9; I

Fig. 11 is a side view, partly in section, of the mechanism shown in Fig. 9'

Fig. 12 is a side trating the beam brake mechanism;

Fig. 13 is a front view of the beam brake cam and associated mechanism;

Fig. '14 is a front view illustrating details of the beam brake operating mechanism;

Fig. 15 is a plan view partly in section 'illus-, trating the beam brake; and

Fig. 16 is a wiring diagram illustrating the electric circuit employed in the machine.

The drawings illustrate a clicking machine operable with freely ducing blanks from sheet material such as leather or fabric.

As shown in Fig. 1 the machine comprises a platen is adapted to support upon its upper face sheet material I2 and a cutting die 14 located. upon the material with its cutting edge down.

Above the platen is located a beam 16 secured View, partly in section, of the View, partly in section, illus-' movable cutting dies for proto a vertically extending post 18 positioned at one side of the. platen and rotatably mounted in the frame 20 of the machine. The beam is movable by means of of the post and across the platen l0 into 0perative position above the die located. upon the sheet material. Operatively connected to the platen is mechanism including toggles 24 for moving the platen upwardly toward the beam to present the die into engagement with the beam, for rolling the platen along the beam in effecting progressive penetration of the cutting edge of the die through the work to produce a blank, and for returning the platen to a rest position.

The platen l0. comprises a substantially rectangular casting 26, the upper portion of which is dished to form a recess 28- within which is positioned a cutting block 29. Preferably the cutting block is composed of a metal core 38 covered with a layer 3| of plastic such as rubber or rubber and fiber material bonded to the case. The block has oppositely curved faces correspending in curvature to that of the bottom face of the recess, each face being a portion of a cylinder of about a sixteen foot radius. The curvature of the block is such as to facilitate the presentation of the workto the beam andto prevent creeping of the die during the cutting operation as the platen is rolled along the face of the beam. The block can be positioned with either of the faces located in the recess and is held in position against lateral movement by metal strips 32 which engage the block 29 and the casting and are held in position byscrews 34. The block is thus provided with two alternately useablework supporting faces. When one face becomes worn the block is reversed presenting a fresh face uppermost.

The lower portion of the platen l0 and most of the operating mechanism of themachine are located within the frame 28 which comprises a hollow box-like casting, the upper portion of which is open to permit heightwise and rolling movement of the platen. The upper portion of the frame isprovided with an apron 36 surrounding the platen Hi and extending close to the ends of the platen but sufficiently spaced therefrom at the-sides to providea clearance for the platen during its rolling movement.

The platen I0 is supported by four toggles as each being located approximately at a corner of the platen. Each toggle 24 (Fig. 6) comprises upper and lower toggle links 45 and 42, respectively, pivotally secured together by pins 44, the upper end of the upper link 40 being pinned to a boss 46 on the underside of the platen and. the lower end of the lower link 42 being pivotally mounted in a boss 48 on a bracket 50 forming a part of the frame.

The toggles 24 at eachend of the machine are in lateral alinement and are arranged to be operated by two toggle levers 52 each having one end pivotally secured to a lower toggle link 42 at 54, and carrying a pin 56 supporting a roller 51 slidably mounted in a guide slot 58 formed in a bracket 60 secured by bolts 62 to the frame.

Outward movement of the toggle levers 52, efiective to straighten the toggles, is obtained by means of a cam 64 mounted upon a cam shaft 66 arranged to engage cam rolls 68 positioned upon the inner ends of the pins 56. The toggles are normally urged toward each other and the rolls 68 are maintained in engagement with the cam 64 by means of a coil spring 10 connecting the ends of arms 1-2 extending from the toggle levers.

a handle 22 about the axis The position of the platen during operation of the toggles is partly determined by two platen control levers 14', Figs. '1, 2, 3 and 6, connected to. opposite ends of the platen along one side thereof. Each lever 14 is pivotally mounted on a boss, [6 on, the frame and has an upper end pivotally connected to one end of a link 18 the other end of which is pinned at 80 to a bracket 82 on the underside of the platen. The lower end of each lever 14 carries a roll 84 positioned in the track 86 in a cam 88 mounted on the cam shaft 66. The cam 88 is so designed that during. the movements of the toggles the control levers 14 are operated to rock the platen about the pins 44 in such manner as to maintain the platen in tilted position during its movement toward the beam in presenting the work and die to the beam and in effecting a rolling movement of the platen along the beam progressively to force the die through the work.

The cam 64 is so designed that the toggle levers 52 on opposite sides of the machine, operate 180 out of phase with each other. In its rest position the platenlilis tilted with one side higher than the otherand corresponding toggles at the high side are more straightened than those onthelow side. Upon rotation of the cam 5d the toggle levers 52' operate further to straighten the toggles 24' onboth sides of the ma-- chine thus raising the platen; Subsequently, the toggles on the high side of the platen are brokenand those on the low side are further straightened to effect a rockingof the platen under the control of the levers 14- aiter which the toggles on both sides are broken returning the platen to rest with the formerly low side now in raisedposition.

Means is provided for preventing movement. of

the platen in an endwise direction to reduce thelikelihood of movement of the die along the platen during the cutting operation. To this end the platen is provided at oppositeends with downwardly projecting plates the outer surfaces of which are engage hardened buttons 92 located upon the frame. The buttons closely engage the plateduring the movement of the pl'atenand serve to. prevent endwise play thereof.

The beam i8- is. a box-like structure comprise ing a hollow casting Gil-having a u-shaped throat. portion at at one end partially surrounding the upper end of the post post by bolts 98' which extend through a cap Hill positioned onthe post. To the underside of the beam is secured a metal plate m2: preferably an aluminum alloy to-form the striking face of the beam.

The post l8 is mounted for rotation about its. axis in a bearing formed by a vertical extension I05- of the frame and a capv H18 clamped. to the extension by bolts l ill. The post has atits lower end a reduced portion- H2 (Fig.v 8) rotatably mounted in an externally threaded sleeve H4 positioned within a Illltf'l-lllfi carried by an extension. HB. of the frame. Above the reduced. portion is a shoulder; i213 which rests upon. a thrust bearing 122 located at the upper. end of the sleeve H4 and arranged tosupport the weight of the post and beam. Rotation of the sleeve H4 results in themovement of the same up. or down relatively to the nut H6 with the conse quent result that the post is raised or lowered, thus providing. for adjustment of the beam heightwise of the machine. The lowermost end of the post. is provided-with; threads 1'24.- upon machined and are adapted to i8; and is clamped: to the which is positioned a stop ring rotation by set screw I28 and arranged to take up the upward thrust of the post.

Conveniently the is controlled by a hand wheel I30 (Figs. 1 and 2) The shaft I32 is operatively connected by gears I36 and I38 to a second shaft I40 carried by brackets I42. The shaft I40 in turn is connected by gears I44 and I46 to a vertical shaft I48. The shaft I48 is mounted on a thrust bearing I50 (Fig. 8) and near its lower end carries a spur gear I52 loosely mounted upon the shaft, its weight being carried by a collar I54 pinned to the shaft. The spur gear is rotated by means of a pinion I56 carried by the shaft and arranged to engage pinions I58 rotatably mounted on a bracket I50, and-havingteeth arranged to mesh with internal teeth I62 on the spur gear. The spur gear has external teeth I54 and corresponding movement of the post I8 and beam IS in a direction heightwise of the platen.

In order to indicate the of the beam I6 heightwise marked out penetration of the die into the cutting block. After a rough adjustment is made the post is then further adjusted heightwise of the frame by a small fraction of an inch to position the beam so that the die will penetrate slightly into the cutting block during the operation of the machine.

The cam shaft the brackets 60 as bracket 60 and secured thereto by bolts I16. A cap I18 threaded intothe sleeve I I4 forms a closure for the sleeve. 7

The cam shaft 66 has a worm wheel I80 (Fig. which is arranged to be driven by a worm I82 on the main drive shaft I84 of the machine. The drive shaft is rotatably mounted in ball bearings I86, I88 and I90, Fig. 5. Bearings I86 which support the outer end of the shaft are carried by a bushing I92 secured to a housing I94 surworm wheel I80, the housing in turn being bolted to a portion of the machine frame at I96. The bearings I88 are supported in a. sleeve I98 carried by the housing I94. The bearings I90 for supporting the inner end of the shaft are carried by a sleeve 200 located in I26 held against a bracket 202 depending from the frame. Loosely mounted upon the ball bearings 204-upon the inner end of the drive shaft is a flywheel 206 arranged to be driven by an electric motor 208 (Fig. 1) by means of a, belt 2I0.

For effecting operations of the drive shaft there is provided a multiple disk type combination clutch and brake assembly 2I2. This assembly comprises a body portion 2I4 surrounding the drive shaft adjacent to the flywheel. The body portion is rotatable with the shaft and is arranged for movement axially of the shaft selectively into clutching engagement with the fiywheel or braking engagement with the frame of engageable with fixed plates 222 carried by bracket 224 positioned in the sleeve I99 and arranged for arresting motion of the shaft at the end of an operation of the machine.

body portion 2I4. A coil spring 240 (Figs. 1 and The actuating lever from clockwise movement (Fig. 7) by a link 246 In order to release the pawl 254,

part of a solenoid 292, which is actuated by manually operable means operation of the machine.

When the solenoid is actuated, the plunger 290 moves in a direction to rotate the lever 214 in initiating a, power the 1i'nk"246 to let 312 soafrahed that, when the p ston isurgi'etl" to the rihtas the chiteh engaged, rapid mvement ofthe'bi'ston will Be preventedil h -Power operation of "the machinej'is initiate manually "operable" mecht 'ism elosel y ass tfe i with the handle 22-and requiringthe 'use ofhoth hands of the-operator in act iiating'sepaifate' switchesarranged'ih series in the cirbuit'tlii ougiij the solenoid 292, as shown in Figs. 9, 10, and il. One of-the switche'sise push buttonswitoh 3M monntedupon a--bracket '315 on the beam. Thj switch is controlled by a member in the form of a lever 3 pivotally mounted on a pin Slqin 91"- recess 320 in-the'-hand1e*and operable byh'and: grip 322 secured-to the lever. A plunger 324fcon nected tothe-lowerend of the lever is arregnge toactuate the switch 314 when the unpr endof the lever is forced towar d the axis oif th e hand le by onehand ofithe operat'oh 1L Mounted on'a 'l'ioriz'bnt 'l plunger 332 or 334 which are arran tral portion a collar 336 pinned to the plunger and platen as above de- :1

he teatime" m disengage:

Tied 6y tieteis rrgied to the eem's 'rtlte.

2 9 2 ren eimpt aw inst described are such that the beam ca n be d of thegope atorfthe har d grip ,q ecteetethe w c hen ised to 'press, one o erationof one of ear bp e inn of fie-th ,e e atpr .i phe m nts arn any likelihood ee e rs ht ush wu e a @11 pge e rs en th li ise-rs t e die"an"d' 'the work dime the p1; s ilre applying.

66 shortly bitter theiletter gonirnegiges tQ :ITQta E, Theliends'df the brake band are; pivotallyseonred whiqhis:pixlotallysecured toe vertically extend- V I, a t eiieveeiae'aifi Etc qf the cam memb rs providing ash' ing portions are effective totengage ,the roll an d mo mted on the shafttin suclfimannerthat the timing of the roll operation will he to efiect movement of the rod shortly after the cam shaft comie ll een ee t on. 3.8".- v p r s te mineitinem e tfs e mesa the term or; e t ap r; ,aaz. 1118mm 4 mences to rotate after the pressure applying opof the switches 332 and 334 current passes from ration has been initiated. Movement of the roll the conductor 466 through contact 484 of relay in a downward direction results in operation of 418 and through a, contact 486 of relay 482 movement of the beam laterally of the platen as solenoid 292. This initiates a power operation the pressure applying operation commences. of the machine as heretofore described.

Shortly thereafter the roll drops off the high part As long as the solenoid 292 remains energized of the cam and eifects release of the brake. 10 the plunger 290 (Fig. 7) is held inwardly and the The beam I 6 is normally movable about the link 218 is held down within the slot 282, with axis of the post by means of the handle 22, and the result that the latch 280 is held in inoperative the construction and arrangement ar such that position, thus preventing actuation of the link tthe beam can be moved angularly in either di- 246 to produce another power operation of the rection until it is clear of the" platen. In order 16 machine. to prevent further movement which might take Solenoid 292 is maintained in energized conthe beam out of th reach of the operator stop dition as long as any one of the switches 3|4,

cured to the post by pin 386. The collar is pro- 20 maintain the coil 410 energized with the result distance in either direction. relay 482 is energized as above described and A Sh wn in i 16. the m tor 208 is supplied current passes from the conductor 466 through from a three-Phase pow Source C p s ng a contact 488 of relay 468 through a conductor power lines 420, 422 and 424 which extend through 490 through a contact 492 in relay 482, and a a magnetic motor starter 426. The starter is conductor 494 to the coil 410 and from thence to provided with three contacts 428, 430 and 432 conductor 414.

which, when a coil 434 is energized, close the cir If the switch 3| 4 is open but either of the power line 420 with one side of a push button relay 468 through the conductor 490, through a stop switch 438 the other side ofthe switch contact 496 in the relay 418 which at that time being connected by a, conductor 440 with one is energized and through a conductor 498, the side of a, push button start switch 442. The conductor 494, through the coil 410 and to the mally closed and the start switch is normally 40 the solenoid is continued to be energized through rent flows through the coil 434 actuating the cuits just described, as long as any of the manumotor starter to close the contacts 428, 436 and ally operated switches is held closed. The pur- 432 and starting the motor. The coil 434 is mainpose of this construction and arrangement is to tained energized by a. holding circuit which exinsure the safety of the operator by preventing tends from the power line 422 through the coil him from tying back or wedging in closed posi- 434, the conductor 444, and a conductor 446, tion one or another of the switches 3l4, 332, 334, through a relay 448, a conductor 450, a contact which is sometimes attempted by an operator leading to the conductor 440, and thence through construction above described after an operator a circuit through the secondary 460 of a transthe resetting of the starting mechanism. former 462 the primary 464 of which is supplied' 5 The safety control mechanism disclosed herein stop switch is depressed to break the holding Having described our invention, what we claim circuit. A conductor 466 connected to one side 50 as new and desire to secure by Letters Patent of of the transformer secondary extends to one side the United States is:

of a relay 468. The relay has a coil 410 which 1. In a clicking 'machine having a beam, a when energized closes a contact 412 to conduct platen for supporting Work to be operated upon, current from conductor 466 through the solenoid means for supporting the platen comprising upcoil 292 and from thence to a condutcor 414 per and lower toggle members, pins pivotally seleading to the other side ofthe transformer curing the members together, and the upper secondary. Extending from the conductor 466 is members being pivotally secured to the platen a branch circuit leading through the switches and t 1ower members being pivotally secured thence to the conductor 414. Another branch means for actuating the toggles in effecting circuit extends from conductor 466 through the movement of the platen toward and away from switch 3M and a coil 480 of a relay 482 and from the beam, and cam controlled means for rocking thence to conductor 414. v r the platen about the pins during actuation of When both relays 418 and 482 are energized through closing the switch a m A M means for moving the platen toward and away from the beam. comprising a drive shaft,--a- -eam=; shaft operatively 'cgnnect edto thedrive shaft,- to'ggls "mounted on ,the a, irame of the machine,- and pivotally connected o-the platen, toggle ac;-

tuating levers each having one, end connected to a toggle, a bracketfupontheirame and having, a guide slottherein, the other end of each toggle having'a pin positioned in the guide; slot,- a: roll carried by each otthe pins andcams upon the camshaft for engaging the rolls to effect actuation of the toggles inpausing operation of the platen, said cams being positioned upon the cam shaft 180? out of phase with each other thereby to ,e'fiect a, roc

ment toward and away from th beam.

a 9k me h uaa beam, a means forfmoving, the platen toward and away from the beam comprising a drive shaft, a cam.

shaftloperatively connected to, the drive shaft,

king of; thejplaten during its movee platen,

toggles mounted on the; frame of the,-machine.,=

and pivotally connected to the platen, toggle 2 actuating leversieach having. one end connected, to a toggle, a bracket upon the jrame having a guide slot therein, the othernend-oj each toggle A having .a. pin positioned in the; guide slot, aroll carried by each of the pins,-. cams-upon the cam 1 shaft. for engaging .the. rollsto effect actuation of the toggles in causing operation of theplaten, said cams being positioned upon the camshaft 180. out of phase witheach other thereby to ment toward and awayirom the beam, a=second cam, upon the cam shaft, a controllever pivotally mounted upon the frame and carrying a roll in engagement With theLsecond mentionedcam, and, a link connecting the control lever and the platen for controlling angular-movement of the platen to cause theplaten to roll along the beam.

4;,1'11 a clic king machinehavinga work supportingv platen, a post positioned at one side of the platen, a beam securedto the post and movable across the platen about the axis of the post, a mounting for the post comprising a: nut -secured to the frame of the, machine, a sleeve making screw thread engagement with the nut,

a bearingfor the postv sleeve providing for rotation of the post relatively to the sleeve, meansfonlimiting movementor the post heightwise of the sleeve, a spur gear, a ring gear continuously. in mesh with the spur gearand movablewith, the sleeveheightwise of the spur gear, and means forrotating the spur gear, wherebythe position of the beam heightwise of the platen is adjusted.

at ;the upper end of the v 5. A clicking machine comprising a beam, -a-

Worksupporting platen spaced heightwise of the beam, said platen comprising a body portion having thereina cylindrically curved recess, and a cutting block having oppositely disposed curved faces corresponding in curvature ,to that of the recess, the cutting blockibeing. positioned :in the recess with one of its curvedfaces inengagement with the bottom of the recess, .and means for having oppositely disbeam in producing 2. In a clicking machine, a beam, a platenf t% that of the recess, the

cutting block being positioned in the recesslwith one of its curved faces en a ement withethe ,bottom' of the recess, and means for moving the, platen toward and away from the beamxand for rolling the platen along the beaminrproducing a'pressure applying operation; upon;.-work carried by the platen. 1

7. A clicking ment of the platen;;and;the:.beam toward and away from each-filler to::causeapressure applying operation upon zworkycarried' by the platen,

and means operable;uponinitiation of operation of the power meansjorapplying the brake.

8. In a; clickin imachine, .a platen, a post mounted for movement angularly about'its axis,

a beam secured to the post; a;drive shaft, means .drive'shaft' and the the post fQrarresting angular movement of the beam;. and means responsive to p rati y .connectingztthe p t a brake'on ,rotationotthe drivashaftifor applying the brake immediately after an initiation oi apower operation-oiztheshaft.

9. A, clickingemachine-scomprising ia' platen, a

verticallyextending post at one side of the platen, a beam ,carriedby :thez-post, meanmmounting the post forangular, movement about its :axis whereby ,the rbeamrcan be moved tacross. the platen, a brake; for arresting angular movement of the post, power; meansv including; a: drivezshaft for effecting relative-movement of theplaten and the beam;=towar,d and aways-from each other to cause, a 31131335511118 applying; operation .upo'nfwork carriedgiby thenplatenmand' means operatively connecting :the: drive shaft andcbrake to apply athebrake wnemoperation of...the'-platen .is ini:

l0. Inv asclicking machine; having a platen, a verticahpost mounted at one side of the platen for movement about ritsaxisyca beam secured to the mesh and: imovablexacross the platen, and means includingra drivershaitafor causing relative mOXLQmBILl'i Of the-platen and beam in chestar timeaut applyingoperation:uponwork carried by thecplaten,:a:brake:ior the post, a ring sely mounted 1 mm the shaft; a link depending from the ring, anzoperativeronnection between the link andathcabrakel memberszsecured to the shait;-fo r preventing: movementxofithe ring 1 axially of theshait a rollpmtheringganda cam on one of h :mQmbQrSL fqrion agingratheroll'. at a predetermined ll me, inthacycleroii ner i n' 0f the link to applynhe, brake.

, lfs'f i l N 1 ZHORATI'OV'. HALL.

shait to caus References Cited in the' fil of this patent UNITED s'rA'r Es PATENTS v Number ff page Date 1,175,015 schlyburt Mar. 14, 1916 1,206,078 Ashton; Nov. 23, 1916 1,513,938' Shea" Nov. 4, 1924: 2,084,335 Freeman, June 22, 1937 2,250,655 Schneider July 29, 1941 aEiqNIm j Number Country Date 

